CLAS physics database search results Measurement E151M2316 EG4 Xiaochao Zheng 2016 cos(theta_pi+) phi(pi+) A_LL Stat. error Syst. error degrees 0.55 102 1.4191 0.9871 0.1072 0.65 90 -1.2023 0.9605 0.0922 0.65 102 1.0891 0.9726 0.0845 0.65 246 0.5852 1.0484 0.052 0.75 102 2.27 0.6762 0.1673 0.75 234 2.2496 0.9006 0.1659 0.75 246 -0.1683 0.9283 0.0324 0.85 54 -1.5939 0.8968 0.1194 0.85 66 1.5232 0.7516 0.1145 0.85 222 0.169 0.9863 0.0324 0.85 234 -0.5677 0.876 0.0509 0.85 246 1.0825 0.8997 0.084 0.85 258 -0.0909 0.7001 0.0307 0.85 270 0.4867 0.8307 0.0463 0.85 282 -2.3478 0.7781 0.1729 0.95 246 0.886 0.9849 0.0709 0.95 258 -0.1955 0.9673 0.0332 0.95 270 -1.1951 0.7129 0.0917 0.95 282 1.3663 0.7709 0.1035 0.95 294 -0.0985 0.763 0.0308 0.95 306 0.4008 0.6944 0.0418 0.95 318 0.3091 0.789 0.0374